Xuecheng Bian

Professor Xuecheng Bian

Research Fellow

Organisation

University of Edinburgh

Research summary

Railway is one of the most important modes of transportation for population and

freight. High-speed railways are undergoing rapid development in many countries in recent decades, but there are many unsolved challenges for fundamental science and innovation in developing sustainable railway substructure. Uneven track settlement will intensify the dynamic impact between train and track, and significantly accelerate the deterioration of the track structure and the granular roadbed, increasing maintenance cost, risk of train derailment and foundation failure. The overall aim of this project is to investigate the roles of inter-particle contact friction and geometric interaction due to ballast particle interlocking in producing the complex bulk responses(such like track settlement) observed in track roadbed. Railway ballast presents many complex phenomena which are still not well understood, e.g. particle deformation and flow pattern with the consequent track settlement under various construction (or maintenance) and traffic loads. Moreover, there are no theories or accepted design guidelines quantifying the influences of key parameters, including particle flow and particle breakage, on the deterioration of railway performance. This research program involves particle-scale numerical modelling and full scale physical model testing on railway ballast, to explore the effect of particle shape and packing structure on the stress distribution and flow pattern that develop in ballasts, and to provide key insights into the ballasted track behaviors. The outputs of this research is beneficial to improvement of design and maintenance methods for ballasted track for high-speed railway.